The Effects of Various Parameters of the Microwave-Assisted Solvothermal Synthesis on the Specific Surface Area and Catalytic Performance of MgF(2) Nanoparticles

High-specific-surface-area MgF(2) was prepared by microwave-assisted solvothermal synthesis. The influences of the solvent and the magnesium precursors, and the calcination atmospheres, on the nanoparticle sizes and specific surface areas, estimated by X-Ray Powder Diffraction, N(2) sorption and TEM analyses, were investigated. Nanocrystallized (~7 nm) magnesium partially hydroxylated fluorides (MgF(2−x)(OH)(x)) with significant specific surface areas between 290 and 330 m(2)∙g(−1) were obtained. After activation under gaseous HF, MgF(2−x)(OH)(x) catalysts underwent a large decrease of both their surface area and their hydroxide, rates as shown by their (19)F and (1)H solid-state NMR spectra. Expect for MgF(2) prepared from the acetate precursor, an activity of 30–32 mmol/h∙g was obtained which was about 40% higher compared with that of MgF(2) prepared using Trifluoroacetate method (21.6 mmol/h∙g).